Isolated and Ice-free

Through geological history, the shorelines of Haida Gwaii have risen and fallen. Many islands that are now above sea level were once below it and vice versa.

During the last ice age, while most of North America was covered in a mantle of ice, some small sections of Haida Gwaii escaped the deep freeze. Some species survived on these “refugia” and have evolved unique characteristics.

Islands are special places for plants and animals. The distinct Haida Gwaii fauna have evolved over thousands of years. Six of the ten native land mammals on the islands are subspecies found nowhere else on earth. This includes the dusky shrew, ermine and pine marten.

The Haida Gwaii black bear (Ursus americanus carlottae) is also unique and is the only species of bear found on the archipelago today. The species has thrived on a rich diet of salmon and hard-shelled intertidal creatures for so long that the bears have developed larger jaws and teeth than their mainland counterparts.

Introduced and Invasive Species

Many common continental species like cougar, wolf and grizzly bear, are not found on the islands at all. Other common species have been introduced relatively recently including - the Sitka black-tailed deer, raccoons, squirrels, beaver and two species of rats.

These introduced and invasive species have been very successful because they have fewer predators and competitors, to the detriment of the native plants, animals and birds.